📝 About This Recipe
The Kartoffelmad is the undisputed king of the Danish lunch table, proving that the humble potato can be elevated to gourmet status. This open-faced sandwich balances the earthy creaminess of waxy potatoes with rich mayonnaise, pungent chives, and the indispensable crunch of crispy fried onions. Built upon a foundation of dense, buttered sourdough rye bread, it is a masterclass in Scandinavian texture and simple, honest flavors.
🥗 Ingredients
The Foundation
- 4 slices Rugbrød (Danish Dark Rye Bread) (dense, seeded variety is best)
- 2 tablespoons Salted Butter (at room temperature for easy spreading)
The Potatoes
- 500 grams New Potatoes (waxy variety like Aspargeskartofler or Fingerling)
- 1 tablespoon Sea Salt (for the boiling water)
- 1 sprig Fresh Lovage or Dill (added to the boiling water for aroma)
The Toppings and Garnish
- 1/2 cup High-quality Mayonnaise (preferably Danish or Hellmann's)
- 1 bunch Fresh Chives (finely chopped)
- 1/2 small Red Onion (sliced into paper-thin rings)
- 1/2 cup Crispy Fried Onions (store-bought or homemade)
- 4 pieces Radishes (thinly sliced for crunch)
- 1 pinch Flaky Sea Salt (to finish)
- 1 pinch Freshly Ground Black Pepper (to taste)
- 1 handful Cress (optional micro-green garnish)
👨🍳 Instructions
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1
Scrub the new potatoes clean, leaving the skins on for maximum flavor and texture.
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2
Place potatoes in a large pot and cover with cold water. Add a generous tablespoon of sea salt and a sprig of lovage or dill.
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3
Bring to a boil, then reduce heat and simmer for 12-15 minutes. The potatoes should be tender when pierced with a knife but still firm enough to slice.
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4
Drain the potatoes and let them steam dry in the pot for 2 minutes, then transfer to a plate to cool completely. For the best results, chill them in the fridge for an hour.
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5
Once cold, slice the potatoes into uniform rounds approximately 1/2 cm (1/4 inch) thick.
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6
Prepare your bread by spreading a thick, even layer of salted butter on each slice of rye bread. This 'seals' the bread so it doesn't get soggy.
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7
Arrange the potato slices on the buttered bread in an overlapping shingle pattern, covering the entire surface of the slice.
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8
Pipe or spoon three to four generous dollops of mayonnaise down the center of the potato slices.
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9
Scatter a generous amount of finely chopped chives over the mayonnaise.
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10
Layer 2-3 thin rings of red onion and a few radish slices over the top for a sharp, peppery bite.
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11
Sprinkle a tablespoon of crispy fried onions over each sandwich for that essential crunch.
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12
Finish with a light dusting of flaky sea salt, freshly cracked black pepper, and a pinch of fresh cress if using.
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13
Serve immediately while the bread is fresh and the onions are crispy.
💡 Chef's Tips
Always use waxy potatoes; starchy ones will crumble when sliced and won't have the desired 'bite'. Don't skimp on the butter—it acts as a moisture barrier between the potato and the rye bread. For the most authentic flavor, boil the potatoes with lovage, which Danes call 'the potato herb'. If you can't find Danish rugbrød, use the densest, darkest pumpernickel or seeded rye available. Make sure the potatoes are completely cold before assembling, otherwise the mayonnaise will melt and become oily.
🍽️ Serving Suggestions
Pair with a cold Danish pilsner or a crisp lager to cut through the richness of the mayo. A small glass of chilled Aquavit is the traditional accompaniment for a festive lunch. Serve alongside other smørrebrød varieties like pickled herring or roast beef for a full 'Koldt Bord'. Enjoy with a side of lightly pickled cucumbers (Agurkesalat) for extra acidity. Sparkling water with a squeeze of lemon is a perfect non-alcoholic pairing.